Valve



C. 30, 1945. G, HOLMES H2,387,792

VALVE 'Filed Dec. 11, 1959 2 sheets-sheet 1 ,fhwentoc mwan HommesPatented Oct. 3,0, 1945 VALVE emma 1. nannies, Minneapolis. assigner toMinneapolis-Honeywell Regulator Company, Minneapolis, Minn., acorporation of Delaware Application December Il, 1939, Serial No.308,541 Y 1e claims. (ci. 23e-4s) This invention relates to fluidcontrollingvalves and more particularly to valves including certainsafety'features.

An object of this invention is to provide a valve of. the modulatingtype operated by a temperaf ture responsive bellows with provision toclose the valve should a leak develop in the bellows capillary tube orbulb.

Another Objectis to provide a valve `of the .above type having means tocause the valve to snap open a certain percentage of its complete rangeof travel.

Another object is to provide a valve which will close automatically whenexcessive pressure arises in the lluid passing through the valve.

Other objects will become apparent from the specification, claims anddrawings.'

Figure 1 is a sectional Aview of a thermostatically controlled gasvalve,

Figure 2 is a sectional 4view of another thermostatically controlled sasvalve,

Figure 3 showsthe bowed snap spring incorporatecl in the valve of Figure2,

Figure 4 is a sectional viewfof a valve designed to close on highpressure within the valve itself,

Figure 5 is ae'section taken on lines 5&5 of Figure i, and

Figure 6 is'aperspective of cams used in' the valve ci Figure 4. I

. One modication of the invention as illustrated in Figure l comprises amodulating gas valve which operates in response` to the temperatureacting on e. temperatureresponsive bulb and is also provided with meansto prevent very small openings of the valve. It is further provided witha safety device which will close the valve should a leak: occur in thetemperature responsive mechanism. One of the dimculties that hasbeenencountered with temperature responsive mechanisms oi this type has beenthat when a leali occurs anywhere in the space occupied by thetemperature nresponsive element, the fluid pressure is reduced and thevalve tends to stay open even on encessivetemperatures. The presentinvention is *adapted to prevent such anunsafe condition.

The valve comprises aI lower valve casing havin@ inlet and outletopenings l2 and la. a valve seat M, and modulating V ports iii. CAnupper valve casing il is suitably secured to the lower casing il byscrews l@ which serve also to clamp a flexible diaphragm il: between theupper andlewer valve castings.

A valve stern 2l carries a .movable valve disc a pressure tight sealwhen the valve is completely closed. The diaphragm I9 is also attachedto the valve disc 22 and to the valve stem 2| so that the centralportion of the diaphragm moves l i up and down with the valve element.The valve stem 2| also carries below the valvedisc 22 a modulating discI5 which cooperates with the V ports I6 to give a modulated gas flow fo'r 'various positions of valve stem 2 The temperature responsivemechanism com prises a bulb 23, a capillary tube 2l, a casing 26ofnoncorrosive material which is screwed to the 4upper valve casing I1and a ilexible metal'bel- Alows 21 also of noncorrosive material whichis solderedat its lowerend to the interior of the casing 2B so that apressure chamber 28 is formed above the bellows 21. The bulb 23, tube24, and

to receive a rod 29 which is secured to the under- -sldeof the bellows2l so that as the bellows is Aexpanded and contracted the rod 29 willchange chamber 28 fare-filled with a suitable volatile liquid. As iswell known, any change in temperature on the bulb 23 will resultin'changes in pressure within the chamber 28 to expand or contract thebellows 21.

The upper end of the valve stem 2| is drilled its position andconsequently position the valve the valve.

atmospheric pressure.

' The common type of gas burner in use todayis capable of maintaining asteady flame over awide range of gas pressures, but if the pressure ingto open the valve. D,

is reduced sumciently unstable combustion will result or the fire willgo out. Consequently ,a

modulating gasvalve should never permit less than a certain minimum gasflow. Means have been provided in the present invention to obtainasudden movement of the valve between closed and a predetermined minimumopen position. 'If gas pressure is admitted to the inlet port l2 therewill be a pressure under the diaphragm I9 tendtemperature acting on bulb23 isA high enough so that the metal bellows 2l is forced downwardly andthe valve is closed. As' the tem- 'peraturev onJthe bulb 23 decreasesthere will be less and less force holding the valve shut and the gaspressure under diaphragm |9will more nearly counterbalance the downward.force. When the pressure under the diaphragm I9 is sunlcient to move thevalve element 22 slightly oil the seat I@ against the force due to thepressure in 22 which seats against'the valve seat I4 to form 55 chamber23 then the pressure under the dia- Assume now that the 'spring restagainst theupper valve housing I1 at M and Il. 1 The valve is 80adjusted that when opening of the valve and this extra'force upward onthe movable parts of the valve will be sumcient tosmove thev valve opena predetermined amount or until the` metal bellows 21 has been movedupward enough so that sumcient pressure is developed in the chamber 28to counterbalance further upward movement of the valve stemf From thisposition of the valve further opening movement will lbe-modulated inresponse to the temperature of the bulb 23 in the usual fashion.

The valve likewise will close suddenly from a minimum open positionbecause as the valve disc closely approaches the seat Il the pressureunder the seat I4 will be so reduced as to'reduce the upward force ofthe gas pressure. Since the valve is closed the spring 43 will assumethe straight position as shown in Figure 2 but will be slightlytensioned upwardly in the middle by the valve stem so that there will bea slight downfurther closing' of the valve further reduces the pressureunder the disc 22 it will snap shut..

This valve also incorporates a safety feature now to be described.lBearing Aagainst the upper interior surface of the upper valve casingI1 is a' helical coil spring 3I which is normally held in a contractedcondition by the sleeve member n which is suppued with a flangeu ati`ts1ower end. A spring latch 3l is suitably secured to the interior ofthe upper valve casing I1 and normally holdsy the sleeve 32v in theposition `shown in `which the spring 3i is contracted. Attached to.

the valve stem 2i is a collar 36 which, should the valve be opened anexcessive amount,`wou1d.

engage the latch 34, force it to the left, and consequently release thesleeve 32. 'The spring 3| will then expand to act as a biasingimeans andmove the sleeve member 32 downwardly to close Y the valve by engagingthe collar 3l. The spring 3| is of sufllcient strength tocounter-balance any gas pressures which would be encountered under thediaphragm I8. A

It will be apparent that any leak which might occur in the' bulb 23,tube 2l, or chamber 2l would result in the valve becoming opened anvexcessive` amount.- 'I'he mechanism just described will serve toautomatically close the valve, thus providing a safety feature forpreventing the valve from remaining in such a position.

.The valve shown in Figure 2 issomewhat simiward Pressure at the endsofthe spring at Il and IB. A spring or this typebecause it is bowedtransversely oii'ers considerable resistance to bending from' theposition shown in Figure 2 to that transversely ilattened longitudinallybowed position shown in Figure 3, but once the center of the spring hasbecome ilat as shown in Figure 3 very little force is required to bendit further. 'I'he spring 43 oifers a'greater initial resistance tobending because it is channeled, but once bent oners only the'resistanceof a leaf spring. The change from one position to the other occurs witha quick or snap action. This characteristic =of the spring -is utilizedhere to obtain a snap action of the valve disc between closed and aminimum open position. This feature is desirable in controlling the gasflowing to gas burners because a minimum initial flow is- 48 serves tosupport the spring and adjust its tension.

As the temperature at the bulb 23 is lowered vthe force exerteddownwardly by bellows 21 will decrease until a point is reached wherethe spring 41 acting upwardly on the lower end oi the valve stem 2l willbe suiilcient suddenly to bend the leaf Ispring ,I3 from the positionshown in Figure 2 to that shown in Figure 3. Further reductions in thepressure on bellows 21 will gradually change the position of the valvebetween this minimum open position and a normal full open position.

Likewise as the temperature of bulb 23 increases the 'valve stem 2i willbe' gradually lowered until spring I3., approaches a straight condition,spring will then tend to straighten out suddenly so that the combinedeffect of spring 43 and the pressure on bellows 21 is ,sumcient tocompletely Il close the valve against the forceof spring 41.

lar to that of Figure 1 with the' exception of the meanslutilize'd toobtain a quick. movement beltween closed and a minimum open positionandconsequentlysimilar reference characters will be used 'on thecorresponding parts. Thelower t valve housing II has inlet and outletports I2 and I3, respectively. The upper valve housing I1 "is secured tothe lower valve housing II by means of the screwsl I8 which serve tocompress a pressure gasket 4I between the upper and lower housings. Thevalve itself consists oi.' a movable valve element 22 which engages thevalve seat I4 to obtain a tight shut olf. A modulating valve disc I5moves over the V ports I8 to give a modulated Aflow of gas for .variousopen positions of the valve. f

The temperature responsive parts o! this valve are the same as thosedescribed'in Figure 1. and

'comprise a bulb 23, tube 2l and chamber.

The safety feature of this valve is exactly the same as described inconnection with the valve of Figure 1. If the pressure in chamber 2lbecomes excessively reduced 4due to a leak. collar 36 on valve stem 2|will be forced upwardly by the spring 41 and releasethe latch 3lpermitting the stronger spring 3I to close the valve.

'I'he valve shown in Figures 4,. 5, and 6 is designed to automaticallyclose in case excessive .presures exist in the fluid passing throughthevalve. One application' of this valve is in the pipe line leading fromthe city water mains to a residence or the like. In -some localities theilre .department greatly increases the pressure inthe city mains in thearea of the city near a fire. Thus-the plumbing nxtlues in residences ofthat area are endangered by this'high pressure. This valve willautomatically isolate the house plumbing from these excessive pressures'when they arise.

The valve comprises a'valve housing II having inlet and outlet ports4 I2and I3, respectively, and a valveseat Il. A movable valve disc 8l has arod 51 secured thereto 5and passing vertically therethrough. The rodl1is slidable in a boss 58 cast into thelower part of the housing 5I.

I As shown in Figure' 2 the outer ends 0I this 75 The rod V81 thereforeserves as a guide'i'or the drical portion 15 at right angles thereto.

valve disc 56. A helical compression spring 59 is carried'around theboss 58 and at all times tends to hold the valve disc 56 in openposition. Bolted to the top of the valve casing is a plate 6l and acover B2. `A gasket 63 lies between the housing 5| and theplate 6i whilethe plate 6| and the cover 62 are separated'by a thin layer of solder64. which serves to form a pressure tight seal between these twoelements. Bolts 66 hold the cover 62 and the plate'l securely to thehousing 5|. Mounted on the plate 6| and sllPDOrted interiorly of thecover 62 is an expansible metal bellows `61 forming a chamber 68 betweenthe bellows 61 and the cover 62.`

Carried above the valve disc 56 on rod 51 is a valve closing element 10which comprises V the plaie portion 1| which is integral with a cylin-The cylindrical portion receives the upper end oi.' the rod 51 which isvsecured to the valve disc-56. Between the element 10 and the plate 6|is a compression coil spring 12. A pair of latch members 1 3 are pivotedin the plate 6| and normally engage a collar 14 on the cylindricalportion 1S f of the closing element 10 to hold the same in its upperposition as shown.

Extending downwardly from the.` top of the metal bellows 61 is a rod 16which carries a collar 11. When the bellows 61 expand upwardly thecollar 11 will engage cam portions of the latch members 13 to releasethe valve closing element 18.

A sufcient gas pressure is introduced to chamber 68 by any suitablemeans (not shown) in an amount sufilcient to counter-balance all normalpressures of'a fluid within the valve casing 5|. Shculdpressure withinthe valve become excessive, however, the bellows 61 will move upwardlyto operate the releasing mechanism of the closing element 10 which willbe forced downwardly by the strong spring 12 to overcome the upwardforce of the lighter spring 59 and close the valvev 56. Also, if the gaspressure within the chamber 68 should become dissipated due to a leaktherein, the tension of the bellows will move'the releasing mechanismupwardly Ito close the valve.

Provision is also made for manually closing the valve and for resettingthe valve to open position after it has been closed either manually orautomatically. 'A hand lever 8|. is secured to the end of ashft 82 whichis pivoted in the valve-l casing 5I.

cams 86 which are rigidly secured to the shaft 82 enable the valve to beclosed manually by rotating the lever 8| clockwise as shown in Figure 4.The

. cams B6 will engage the top of valve disc 66 to force it downwardlyagainst the action of the spring 59. The upper part of the rod 51 willslide within the valve closing element 10, the valvel closing elementremaining stationary. The valve Vwill then remain closed as long aslever 8| is in the element 10 to raise the closing element 18 until thelatches 13 have again engaged the collar 14 at the top of the closingelement 18. It should be noted that incase excessive .pressure stillexists it will be impossible to open' the valve. If excessive pressureexists, the latches 13 will still be in an outward position in which itwill be impossible for them to engage' the collar 14 at the top oftheelement 18. Asthe large cams 81- are lifting'the closing element 1li,the small cams 86 prevent opening of the valve disc 56. In this way itwill be seen that what is known as a trip free valvehas been providedbecause it impossible to hold the valve in open position when a highpressure exists inthe supply line to the valve.

While several modifications have been shown and described it is to beunderstood that the scope of this invention is to ,be determined only bythe appended claims.

I claim as my invention: A

l. In combination, a control device normally movable between a safe rstposition and an active second position, direct acting conditionresponsive pressure means indicative of temperature normally `forpositioning said device between valve member when the pressure of thevolatile iyluid within the metallic bellows is reduced ex. cessively.

3. An automatically operable valve, comprising, a movable valve member,a condition responsive element adapted to control the position of thevalve member between closed and a normal full open position, a diaphragmacting on the valve member and responsive to the pressure of the iiuidon the high pressure side of `the.valve for causing the valve member tomove between closed and partly opened positions with a quick action,

' a spring adapted to close the valve member, and

v A gland 83 cooperates with packing '8l to prevent leakage around theshaft 82. The

a latch normally for holding the spring in inoperative positionreleasable by the condition re sponsive element when in an excessivelywide open position.

4. A valve comprising a movable valve member, means tending to move thevalve member toward open position, a condition responsive elementadapted to position the valve member against the action of said means, atransversely bowed leaf spring for imparting a snap action to the valvemember between closed position and a minimumy open position, biasingmeans for positively closing the valve, latching means normally forholding the biasing means in inoperative position, said latching meansbeing releasable bythe valve member when the valve member assumesanexcessively wide open position. 5. In combination, a control devicemovable between a safe rst position and an active second position, saiddevice being biased to said second position, resiliently actuated meansfor moving said device to said rst position, restraining means normallyfor restraining said resiliently actuated means in a position in whichit is inoperative to move said control device to said rst position.first cam means rotatablehen a shaft for moving said resilientlyactuated means to a position in which engagement with saidA restrainingmeans may be effected, andsecvond cam means rotatable on the sameshaftas said rst cam means for holding said device in lsaid rst positionuntil said restraining means engages said resiliently actuated means.

Y 6. In combination, a control device movable between a safe positionand an'active position, resiliently actuated means for moving saiddeviceto said safe position, restraining means normally foi' restraining saidresillently actuated means in a position in which it is inoperative tomove said device tosaid safe position, a strain release connectionbetween said resiliently actuated means and said control device, arotatable shaft, and cam means carried by said shaft and operative uponrotation of said shaft to move said resiliently ac- Vtuated means intoengagement with said restraining means and simultaneously extend said Vconnection so as to eect engagement of said resiliently actuated meansand said restraining means without movement of said control device fromsaid safe position, said vstrain release -connection being eiiectiveupon said resilieritly actuated means being held by said restrainingmeans and said cam means being moved to e, position permittingcontraction of said` connection to move said control element to saidactive position.

` '1. In combination, a valve movable between a safe and an activeposition, resiliently actuated 'means for moving said valve to said safeposition, restraining means normally for holding said resilientlyactuated means in a position in which it is inoperative to move saidvalve to said safe position, a iirs/t-pair oi.' cams for moving saidresilientlyV actuated means to a position in which engagement with saidrestraining means may be effected, and a second' pair of cams forholdingv said valve in said safe position until said restraining meansengages said resiliently actuated means.

8. In combination, a valve casing, a valve seat l therein. a valvemovable to and away from said seat, biasing means urging said valve awayfrom asoman biasing means is effective to move said-control device backto said safe position.

10. lIn combination, a flow control device movable towards and away froma safe position, a movable wall adapted to be exposed to the pressure ofthe controlled fluid, means connecting said wall and said control deviceand effective to cause the pressure ot said uid acting against said wallto urge said flow control device away from said safe position, means forresisting movement of said wall caused by the uid pressure, biasingmeans for moving said ow control device to .said safe position, saidbiasing means being capable of exerting suilicient force to move saiditlow control device to said safe position against vthe effect of saidiluid pressure on said movable wall, a latching arm for restraining saidbiasing means,y saiddatching arm being biased into v latching position,and means operative upon said i adapted to be exposed to the pressure oithe controlle'd fluid, means connecting said wall and said valve andeffective to cause the pressure of said fluid acting against said wallto urge said valve towards open position, means for resisting movementof said wall caused by the :duid pressure,

f biasing means i'or closing said valve, said biassaid seat, a valvestem xed tofsaid valve, a sleeve coaxially arranged with said valvestem, said sleeve at' all times surrounding a portion of 'said .stem tothereby guide said valve, a spring stronger than said biasing meansconnected withsaid sleeve for closing said' valve, a shoulder portion onsaid sleeve, a latch cooperable with said shoulder portion forreleasably retaining said spring l in an inactive position, and meansresponsive to a controlling condition for causing said latch to` releasesaid shoulder whereupon said spring will'k close said valve.

9. In combination, a flow contro1 device movable towards and away from asai'e position, a movable wall adapted to be exposed to the pressure ofthe controlled uid, means connecting said wall and said control deviceand eilective to cause the' pressure of said iluid acting against saidwall to urge said tlow contro1 device away from said safe position,means for resisting movement of said wall caused by the iluidpressure,biasing means for moving said now control device to said safe position,said biasing means being capable of exerting su'incient force to movesaid flow control device to s aid safe position against the eilect ofsaid iluid pressure o'n said control the position of 'said valve memberbetween ing means being capable of exertingsuiilcient Aforce to closesaid valve against the eiIect o! said y fluid pressure on said movablewall, means for revtive whereby said biasing means is eifective to movesaid control device baciato-'said safe position.

12. In combination, a control`device normally movable between a safefirst position -and an active second position, direct acting conditionresponsive pressure means indicative of tempera-l ture normally forpositioning said device between said iirst and second positions, biasingmeans for moving said device to said rst position, means for restrainingsaid biasing means, 'and means for rendering said restraining meansinoperative if said pressure means moves to a point at whichl saiddevice would be beyond saidv second vposi-` tion.

13. A valve comprising a movab valve mem- 'ber, a condition responsiveeleme t responsive to a condition remote from said valve and independentof the Vcondition of the `valved iluid, said condition responsiveelement being adapted to closed and normal full open positions inaccordance withthe value of said condition; snap acting resilient meanscooperating with'the condition responsive element for causing the valvemember to move through part of its range o! movement ,with a snapaction,vmeans independent of the condition responsive element forclosing the valve, and a` latch releasable by the valve memberwhen in.an excessively wide open position to releasethe independent means butnormally holding the independent means in inoperative position.

aaezvca 14. A control apparatus comprising a temperature responsivevariable volume chamber, an op erable device controlled by the normalexpancomprising a latching element movable substan- 10 tiallytransversely of the path of movement of said device, and meanscontrolled by the contraction of said chamber beyond a predeterminedlimit of normal contraction to cause said latching element .to be movedtransversely out of its l5 latching position.

15. A control apparatus comprising a variable volume chamber containingtemperature responsive fluid in a quantity suiiicient to limit thecontraction of said chamber in the normal operation 20 or saidapparatus, an operable device controlled by the normal expansion andcontraction of said chamber, spring means operable to contract saidchamber beyond said normal limit of contraction upon the loss of uidfrom said chamber, a pre- 25v loaded spring operable when released tomove said operable device in the direction in which it is moved by thenormal expansion of said chamber, means normally retaining said pre*-sion and contraction of said chamber in response/, 7

loaded spring in a condition in which it has no eiect upon the positionof said device, and means controlled by the contraction of said chamberbeyond said normal limit of contraction to release said pre-loadedspring.

16. lAv thermostatic valve comprising a movable valve member having avalve stem, a variable volume chamber containing temperature responsiveuid and operatively connected to said valve stem, biasing means opposingsaid variable volume chamber and\blasing saidl valve to a rst position,said variable volume chamber being operative upon expansion thereof dueto a change in the temperature of said fluid to move said valve membertowards a second position against the action of said biasing means, apre-loaded spring operable when released to move said valve membertowards said second position in the dil rection in which it is moved bythe normal expansion of said chamber, means normally retaining saidpre-loaded spring in a condition in Whichit has no eiect upon theposition of said valve member, and means including an element associatedwith said valve stem operative upon the contraction of saidchamberbeyond its normal range of contraction to release saidpre-loadedV spring.

' GIEFORD I. HOLMES.

